Apparatus for applying bronze powder to a continuously moving paper web

ABSTRACT

For applying bronze powder to parts of a continuously moving paper strip particularly a cigarette paper strip, which are provided with an imprint in adhesive, a roller with a novel surface is utilized, a second roller with a specially formed surface being used thereafter as a means for removing surplus bronze powder from the paper strip.

United States Patent Freiwaltl et a1.

[54] APPARATUS FOR APPLYING BRONZE POWDER TO A CONTINUOUSLY MOVING PAPER WEB [72] Inventors: Heinz Freiwald, Bunningstedt; Karl- Heniz Eggert, Ahrensburg, both of Germany [73] Assignee: B.A.T.-Cigaretten-Fabriken GmbII,

Hamburg, Germany [22] Filed: April 14, 1970 [21] Appl. No.: 28,435

[52] U.S.Cl. ..118/57, 118/118, 118/262 [51] Int. Cl. ..B05c 1/08, BOSc 11/02 [58] Field of Search ..118/262, 118, 637, 223, 119, 118/109, 57, 244, 249, 308; 117/19, 111 F,

[56] References Cited UNITED STATES PATENTS 1,851,761 3/1932 Everett ..117/111 R UX [451 Dec. 12,1972

3,122,453 2/1964 Montgomery ..118/308 X 3,125,465 3/1964 Kuts ..118/262 X 2,748,019 5/1956 Schramm. ..1l7/19 X 1,883,535 10/1932 Burnett ..118/57 X 247,582 9/1881 Sargent 18/1 19 1,326,362 12/1919 Mattison ..118/119 FOREIGN PATENTS OR APPLICATIONS 4,320 1897 Great Britain .L ..118/249 Primary Examiner-John P. McIntosh Attorney-Roylance, Abrams, Kruger, Berdo and Kaul [57] ABSTRACT For applying bronze powder to parts of a continuously moving paper strip particularly a cigarette paper strip, which are provided with an imprint in adhesive, a

roller with a novel surface is utilized, a second roller with a specially formed surface being used thereafter as a means for removing surplus bronze powder from the paper strip.

3 Claims, 9 Drawing Figures PATENTEB um 12 I972 SHEET 2 [1F 5 PATENTED um 12 I972 SHEET '4 [IF 5 Fig. 5

Fig. 6

PATENTEI] DH; 2 I 3. 705 S68 sum 5 OF 5 fig; 1

APPARATUS FOR APPLYING BRONZE POWDER TO A CONTINUOUSLY MOVING PAPER WEB BACKGROUND OF THE INVENTION ing an applying roller connected to a rotary drive and another roller, likewise connected to a rotary drive, for removing the excess bronze powder from the strip.

Appliances of this type are used in the cigarette industry for producing an imprint on the cigarette paper before it is laid around the strand of tobacco. The paper strip is first provided with an imprint in an adhesive producing only slight coloration, in the form of the final imprint to be subsequently obtained. Bronze powder is then applied to the part of the paper strip provided with the adhesive imprint and adheres to that part. Excess bronze powder is removed from the strip of paper, particularly from the parts which have not been provided with the adhesive imprint. A roller provided with a felt covering has hitherto been used for applying the bronze powder. This roller receives the bronze powder from a transfer roller, the periphery of which is likewise covered with felt. In order to remove the excess bronze powder, in known machines the paper strip runs over ,a roller the surface of which is formed by a plush covering.

Known appliances have the disadvantages that the felt and plush coverings of the rollers are subject to heavy wear. These appliances must therefore be continuously supervised. In order to ensure that this supervision is actually carried out, these appliances have only a relatively small reservoir, into which only a narrow portion of the periphery of the applying roller penetrates at one time. It is not advantageous for the reservoir, which is open at the top, to be filled to a greater extent, since this would entail the transfer of an excessive amount of bronze powder to the applying roller and consequently to the paper strip. On the other hand, the amount of bronze powder in the reservoir must not substantially decrease, since otherwise insufficient bronze powder would be transferred to the applying roller and consequently to the paper strip. The need for constant supervision of the amount of bronze powder contained in the apparatus ensures that the rollers, the coverings of which have to be replaced very frequently, will also be continuously inspected.

SUMMARY OF THE INVENTION The aim of the invention is to provide an apparatus of the type first described above, which requires practically no maintenance. In order to solve this problem, in an apparatus of the type inquestion the invention provides for the applying roller to have a peripheral surface of polyamide or of a plastics material having a similar surface. The applying roller preferably cooperates with a transfer roller which likewise has a peripheral surface of polyamide; according to another feature of the invention provision is made for the rotation of the applying roller to take place in a direction such that at the application point its periphery runs in the opposite direction to that in which the paper strip runs andthat the transfer roller in turn rotates in the opposite direction to the applying roller.

The polyamide cover with which the applying and transfer rollers are provided has a macroscopically smooth surface,which in contrast to the felt covering of the applying roller in theknown apparatus, appears completely closed. The surface of the polyamide cover of the applying and transfer rollers is however not as smooth as a polished metal surface. In any case the polyamide covering of the applying and transfer rollers ensures that the bronze powder is taken from the reservoir and transferred to the applying roller, and from the latter to the strip of paper, substantially more evenly than in conventionalapparatuses. Practically no wear of the covering of the applying and transfer rollers,

consisting of polyamide or a similar plastics material,

can be detected. The supervision of the applying and transfer rollers which is otherwise necessary to ensure that they are capable offunctioning is therefore not required.

In order to improve still further the apparatus according tothe invention it is in addition proposed to replace the plush covered roller used to brush the ex cessfrom the stripby a device which is likewise not.

subject to wear and therefore works without maintenance. Whereas the plush roller works by brushing the excess from the paper by means of the plush hairs, the invention proposes that after passing over the applying roller the paper strip should. run over a device by which the strip is caused to vibrate over a short distance, so that the excess bronze powder is shaken off. For this purpose, at the outlet of the apparatus there is disposed a roller which is likewise connected to a rotary drive and which has a smooth peripheral surface provided with cup-shaped recesses. The strip is pulled over this roller, which in the region of contact runs oppositely to the direction of movement of the strip. The side of the strip provided with the imprint faces the roller. The brushing operation which hitherto was customary had the result that the imprint on the cigarette paper had unsharp edges or appeared smudged. The apparatus according to the invention also eliminates this disadvantage.

Further advantages and features of the invention will be seen from the claims and from the following description and the drawings, in which a preferred embodiment of the invention is illustrated as an example, and

in which:

FIG. 1 is a plan view of an apparatus according to the invention, illustrated in a simplified manner,

FIG. 2 a side view of part of the apparatus shown in FIG. 1, likewise illustrated in a simplified manner,

FIG. 3 is a similar side view to FIG. 2, but with the illustrated part of the apparatus shown cut open,

FIG. 4 shows a detail of a part of the apparatus of the invention, viewed from above,

FIG. 5 is a side view of an applying roller according to the invention,

FIG. 6 a plan view of the roller shown in FIG. 5,

FIG. 7 a side view of a transfer roller according to the invention,

FIG. 8 a plan view of a roller according to the invention for removing excess bronze powder, and

FIG. 9 a side view of the roller shown in FIG. 8, partly in section.

An apparatus 10 according to the invention, as illustrated in FIGS. 1, 2 and 3, contains a chamber 12 which at the top is covered at least partly by a guide 13 for the paper strip P. In the top part of the chamber 12 an applying roller 14 is mounted for rotation, while its shaft 16 projects out of the apparatus and on the outside can be provided with a pinion 18 which is driven by a motor and gearbox (not shown). The roller 14 is provided with a cover of polyamide. In one practical embodiment the material used for the cover 15 is the product marketed by the firm AKU under the name Polyamide B. Other commercial names are Nylon 6 or Etamal.

Under the roller 14 a transfer roller 20 is mounted which has an axis parallel to the axis of shaft 16 and is driven similarly to the roller 14. The transfer roller 20 is likewise provided with a cover 21 of polyamide. The arrangement of the rollers 14 and 20 or the thickness of the polyamide covers 15 and 21 are so selected that between the covers 15 and 21 a gap is left which is larger than the average particle diameter of the bronze powder to be transferred from the roller 20 to the roller 14. With customary bronze powders used for printing cigarettes, with particle sizes in the range from about 80 to 90 microns, a distance of about 0.1 mm has been found convenient.

A link 22 projecting downwards into the chamber 12 is mounted for rotation on the shaft of the roller 14. The link 22 is in addition provided with a cutout 23, which is in the form of a slot and is engaged by an eccentric 24 joined fast to the roller 20. On the rotation of the roller 20 the link 22 is therefore rocked to-andfro. Pins 26 which are fastened on the bottom end of the link 22, and which are directed substantially parallel to the axes of the rollers 14 and 20 and extend over practically the entire width of the chamber 12, consequently stir the bronze powder situated at the bottom of the chamber. On the link there is also fastened a third pin 28 which lies parallel to the two pins 26 but has a length equal to only about one-third of their length. The pin 28 is provided with an extension 30 which projects through the link 22 and engages an aperture 32 which connects the chamber 12 at its bottom to an adjoining chamber 34 serving as reservoir. The size of the aperture 32 can be varied by means of a slide 42. The slide 42 is moved by a screw 36, the knurled head 38 of which is situated on the outside of the apparatus 10. The screw 36 is guided in a block 41 and a bracket 40. The parts 40 and 41 are fastened on the wall of the chamber 34.

A chamber 44, which in the bottom region can be in communication through an aperture 45 with the chamber 12, adjoins the latter. In the chamber 44 a roller 46 is mounted, the shaft 48 of which is likewise connected by a pinion 50 to a drive (not shown). On its peripheral surface the roller 46 has blind bores 48 which are in the form of flat cups. The blind bores 48 are distributed regularly over the entire width and around the periphery of the roller 46. It is however not necessary, for example, for the diameter of the blind bores 48a to be larger than the distance between the blind bores 48b and 480 lying in the adjoining row. In one form of construction which is in use the diameter of the blind bores is smaller than the distance between neighboring blind bores the centers of which lie on a generatrix. The distance between two neighboring generatrices on which the center points of blind bores lie is approximately of the order of magnitude of two diameters of the blind bores which in this form of construction are identical.

In the operation of the apparatus of the invention the paper strip P is pulled through the apparatus by a device which is known in itself and is not illustrated in the drawings, and which may be disposed on the lefthand side of FIG. 2. The paper strip P entering the apparatus has been provided with a adhesive imprint in an inking mechanism and is in tangential contact with the polyamide cover 15 of the applying roller 14. The applying roller runs in the direction of the arrow shown in FIG. 2 and from the transfer roller 20 receives bronze powder which is contained in the bottom part of chamber 12. The aperture 32 is adjusted by means of the slide 42 so that only the portion of the cover 21 of the roller 20 situated at the bottom at a given moment is immersed in the bronze powder, which is stirred by the pins 26, 28. The bronze powder thus received by the polyamide ring 21 is transferred to the polyamide ring 15 on the roller 14. The paper strip running through the apparatus strips the powder off the polyamide cover 15. The paper strip P is then in contact with the roller 46. Contact with the roller 46, which is provided with the blind bores, has the effect that the paper strip P is caused to vibrate over the chamber 44 in its portion lying between the boundary wall of the chamber 12 and the roller 46, whereby excess bronze powder is shaken off the paper strip and drops into the chamber 44. In order to reduce the production of dust, a sieve plate (not shown) may be disposed in this portion of the chamber 44, this sieve plate being known in itself and being vibrated by the link 22. In addition to the vibration of the paper strip, which is caused by contact with the roller 46, this roller also applies to a certain extent a scraping action by means of its blind bores 48; the greater part of the excess bronze powder is however shaken off by the vibrations or fluttering of the paper strip I.

What we claim is:

1. An apparatus for applying bronze powder to adhesive coated areas of a continuously moving paper strip comprising a chamber;

a quantity of bronze powder at the bottom of said chamber;

a transfer roller having a macroscopically smooth plastic surface, said roller being mounted for rotation in said chamber about a longitudinal axis of said roller, the lower surface of said roller being in contact with the bronze powder;

an applying roller having a macroscopically smooth plastic surface, said roller being mounted for rotation in said chamber about a longitudinal axis, said applying roller further being mounted in a predetermined spaced relationship relative to said transfer roller whereby bronze powder from said transfer roller is transferred to said applying roller;

means for rotating said roller;

guide means mounted on said chamber for supporting the paper for movement above and in contact with the upper surface of said applying roller,

means for stirring said quantity of bronze powder at the bottom of said chamber comprising a link pivotally mounted in said chamber for limited rotary movement about the axis of one of said rollers;

a pin having a length substantially the width of said chamber, said pin being substantially parallel to the longitudinal axes of said rollers and being carried at one end by said link, said pin being located at the bottom of said chamber and immersed in said quantity of bronze powder; and

means for imparting reciprocatory motion to said link to move said pin and stir said bronze powder; and

means for vibrating the moving paper strip over said chamber after the strip has passed the contact point with said applying roller,

2. An apparatus for applying bronze powder to adhesive coated areas of a continuously moving paper strip comprising:

a chamber;

a quantity of bronze powder at the bottom of said chamber;

a transfer roller having a macroscopically smooth plastic surface, said roller being mounted for rotation in said chamber about a longitudinal axis of said roller, the lower surface of said roller being in contact with the bronze powder;

an applying roller having a macroscopically smooth plastic surface, said roller being mounted for rotation in said chamber about a longitudinal axis, said applying roller further being mounted in a predetermined spaced relationship relative to said transfer roller whereby bronze powder from said transfer roller is transferred to said applying roller;

means for rotating said roller;

guide means mounted on said chamber for supporting the paper for movement above and in contact with the upper surface of said applying roller; means for stirring said quantity of bronze powder at the bottom of said chamber; and means for vibrating the moving paper strip over said chamber after the strip has passed the contact point with said applying roller, said means for vibrating comprising a roll mounted for rotation about an axis parallel to the moving strip of paper, said roller being in contact with the lower surface of said paper, said roller having a plurality of blind bores extending radially inwardly from the contacting surface thereof. 3. In an apparatus for applying bronze powder to selected adhesive-coated areas of a continuously moving paper strip and for removing excess powder a plurality of radially inwardly extending recesses, said roller being rotatably mounted in contacting relationship with said strip. 

1. An apparatus for applying bronze powder to adhesive coated areas of a continuously moving paper strip comprising a chamber; a quantity of bronze powder at the bottom of said chamber; a transfer roller having a macroscopically smooth plastic surface, said roller being mounted for rotation in said chamber about a longitudinal axis of said roller, the lower surface of said roller being in contact with the bronze powder; an applying roller having a macroscopically smooth plastic surface, said roller being mounted for rotation in said chamber about a longitudinal axis, said applying roller further being mounted in a predetermined spaced relationship relative to said transfer roller whereby bronze powder from said transfer roller is transferred to said applying roller; means for rotating said roller; guide means mounted on said chamber for supporting the paper for movement above and in contact with the upper surface of said applying roller; means for stirring said quantity of bronze powder at the bottom of said chamber comprising a link pivotally mounted in said chamber for limited rotary movement about the axis of one of said rollers; a pin having a length substantially the width of said chamber, said pin being substantially parallel to the longitudinal axes of said rollers and being carried at one end by said link, said pin being located at the bottom of said chamber and immersed in said quantity of bronze powder; and means for imparting reciprocatory motion to said link to move said pin and stir said bronze powder; and means for vibrating the moving paper strip over said chamber after the strip has passed the contact point with said applying roller,
 2. An apparatus for applying bronze powder to adhesive coated areas of a continuously moving paper strip comprising: a chamber; a quantity of bronze powder at the bottom of said chamber; a transfer roller having a macroscopically smooth plastic surface, said roller being mounted for rotation in said chamber about a longitudinal axis of said roller, the lower surface of said roller being in contact with the bronze powder; an applying roller having a macroscopically smooth plastic surface, said roller being mounted for rotation in said chamber about a longitudinal axis, said applying roller further being mounted in a predetermined spaced relationship relative to said transfer roller whereby bronze powder from said transfer roller is transferred to said applying roller; means for rotating said roller; guide means mounted on said chamber for supporting the paper for movement above and in contact with the upper surface of said applying roller; means for stirring said quantity of bronze powder at the bottom of said chamber; and means for vibrating the moving paper strip over said chamber after the strip has passed the contact point with said applying roller, said means for vibrating comprising a roll mounted for rotation about an axis parallel to the moving strip of paper, said roller being in contact with the lower surface of said paper, said roller having a plurality of blind bores extending radially inwardly from the contacting surface thereof.
 3. In an apparatus for applying bronze powder to selected adhesive-coated areas of a continuously moving paper strip and for removing excess powder therefrom, the combination comprising means for supporting and guiding a moving paper strip; means for contacting said strip and for applying bronze powder to the strip including the adhesive coated areas thereof; means for supplying powder to said means for applying; and means for vibrating said strip to remove excess powder, said means comprising a roller having a smooth exterior surface and having a plurality of radially inwardly extending recesses, said roller being rotatably mounted in contacting relationship with said strip. 